In order to carry out hydrogenation reactions, it is common to use catalysts based upon cobalt and/or nickel. In particular, such catalysts are used in the conversion of nitriles (including dinitriles) to corresponding amines. Primary amines are formed by reductive amination wherein aldehydes or ketones and ammonia are hydrogenated in the presence of such cobalt or nickel catalysts. It is known to use Raney cobalt or nickel for such reactions.
In particular, such compounds as diethylaminoacetonitrile undergo this reaction in the presence of Raney nickel to form the corresponding diamine. However, the yield is only 37% which is too low for a commercially viable process. This reaction and yield is set forth in Winans and Adkins (Am. Soc. 55, 4167 (1933)). However, even this yield has been found not readily reproducible (cf. Houben-Weyl 11/1, page 563).
GB-PS 745 684 describes a process for the production of N,N-dialkylaminoethylamine by catalytic hydrogenation of N,N-dialkylaminoacetonitrile at elevated pressures and temperatures below 110.degree. C. Raney cobalt is used and the process, which requires liquid ammonia, produces a yield of 92%.
In general, a relatively complete description of reductive amination of carbonyl compounds etc. with Raney nickel catalysts is set forth in Houben-Weyl, Methoden der organischen Chemie, Stuttgart 1957, volume XI/1, page 602 et seq. In spite of their excellent activity, Raney nickel and cobalt catalysts have not been fully adopted in industry. One of the main reasons for this is that such catalysts are difficult to handle, can only be used in suspended form and not as fixed bed catalysts, and are relatively complicated to prepare.